Argh! When in doubt, believe the Tek manual. I read that a 2 ohm load was sufficient, resulting in 2.5A draw. Wrong. Added a second 2 ohm on the options line (because the fusing on the 2 exposed +5VD lines is 5A each). PSU now working perfectly. That was a huge waste of time. At least I learned a lot about the PSU. :)
